Active chilled beam systems for tropical buildings

The goal of this work package is to design active chilled beams (ACBs) as well as hybrid VAV-ACB systems for tropical environments. The research focuses on modelling, control and optimization of novel ACB systems and processes. Entrainment ratio is our main concern since it is an important performance indicator of an ACB unit. Computational Fluid Dynamics (CFD) simulation was used to facilitate the ACB design and evaluate its performance. Based on the CFD simulation results, various nozzle geometries were investigated. The present CFD simulations evaluate the entrainment ratio of nozzles with different geometries, including circular, circular-lobed, elliptic, elliptic-lobed, etc. These nozzle candidates have different advantages in different ACB designs. From the CFD investigation of nozzle geometry, it was found that the entrainment ratio of the nozzle can be improved by modification of its geometry. The lobed nozzles are good candidates to be applied in ACB to enhance entrainment. We have designed an ACB chamber, established a testing platform to evaluate the ACB performance, and have studied the mechanism of the ACB controller.